Microfluidic technologies are widely used in bio-chemical analysis, such as micro-pump, micro-valve, micro-filter, micro-mixer, micro-channel, and micro-sensor. They are mostly used in micro-chips for processes such as sample pre-processing, mixing, transmission, separation, and detection. The use of micro-fluidic chips in biological or medical diagnosis and analysis has the advantages of saving both time and manpower.
U.S. Pat. No. 6,073,482 disclosed a fluid flow module having a micro-channel with a sensor. By opening and closing the valves, the module conducts three types of fluids (i.e. calibrant, buffer, and analyte) into the micro-channel. It allows for analyte sample flow therethrough while providing a site for the location of a sensing elements or elements therein to detect analyte presence and/or concentration. The disclosed module can be used as a micro bio-chemical diagnosis kit.
Similarly, U.S. Pat. No. 6,695,147 disclosed an absorption-enhanced differential extraction device. As shown in FIG. 1, the H-shaped micro-channel structure 100 of the device can be used to extract or separate from a solution.
Lee et. al. (Micromachined Pre-focused 1×N Flow Switches for Continuous Sample Injection, J. Micromech. Microeng., 11(2001), pp. 567-573) disclosed a micro-channel structure using the fluid-dynamic from a micro-pump to inject various samples into various outlets for connecting to different fluidic analysis chip.
Powers et. al. (A Microfabricated Array Bioreactor for Perfused 3D Liver Culture, Biotechnology and Bioengineering, 78(2002), pp. 257-269) disclosed a 3D micro-structure using continuous cyclic flow to cultivate the liver cells from a mouse and observe the changes.